What's the point on non-geologists or non-petroleum engineers believing/guessing there is oil without any type of scientific knowledge in this regard at all?
You believe things like religion and spirituality. You either KNOW there is oil, or you DON'T in which case you hire or get the scientific community to do initial drilling and test for oil reserves
The government says seismic data shows more than a billion barrels of oil lie off Sri Lanka`s northwest coast, though no reserves have yet been proven.
Seems initial surveying show oil reserves, but since none has been proven, it's just a waiting game until the actual exploration happens. According this article and a few others I found, it seems the gov't is bidding other companies to begin exploration pretty soon, then you can KNOW for sure instead of believing or guessing.